Various normal and malignant mouse tissue endpoints will be used to investigate the efficacy of combining certain drugs with radiation for the treatment of cancer. The endpoints which will be used will be, for tumors: cell survival curves using both in situ and in vitro irradiation, delay in regrowth and tumor cure; and for normal tissues: early and late reactions in the irradiated leg, radiation pneumonitis, radiation myelitis and radiation nephritis. The drugs to be used will be first, the pyrimidine analog 5-bromo-2'-deoxycytidine (BCdR), which will be investigated both from the point of its ability to sensitize lung metastases by i.v. infusion and for its deamination in vivo. Second, the ability of the drugs metronidazole and Ro 7-0582 to sensitize only hypoxic cells to irradiation will be investigated in single and multiple fraction dose protocols. In addition, various host treatments which affect the ability of cells to produce blood-borne metastases will be investigated. These will include radiation, cyclophosphamide and C. parvum.